<!-- ajax get tags -->
<input type="text" list="tag_list" placeholder="标签" id="tag" class="inputM" />
<input type="text" placeholder="标题" id="title" class="inputM" style="width:20em;" />
<datalist id="tag_list">
 <option label="水" value="水" />
 <option label="二手" value="二手" />
 <option label="询问" value="询问" />
</datalist>